100th Birthday Bash!

If you’re in town on Sunday 9th June, I strongly recommend coming along to this! The Natural History Museum is having its 100th Birthday celebration with an all day series of events. There’ll be new spaces and exhibits opening, including the new gardens they’ve been building for some time, and so there’s plenty to explore that will be new, and partly outdoors on a (hopefully) lovely day. (See here for an LA Times article on some of the changes.) As the day draws into the evening, there’ll be a real party brewing, with bands, DJs, bars, and so forth (see below). Kicking off the evening part of the proceedings at 6:30pm will be a talk and Q+A with JPL’s Adam Steltzner (of the Mars Curiosity Mission), in a spot hosted by me.

Adam’s a great guy, with lots of interesting things to say and a great sense of […] Click to continue reading this post

SCSS Report

scss_may_2013Friday’s Southern California Strings Seminar was a success! Thanks to all who came, who spoke, and the UCLA organizers. I enjoyed all four talks that were put on, and learned a lot from each. (Sera Cremonini is giving her nice talk about duals of hyperscaling violating theories in the photo.)

I was particularly pleased about the talk by Daniel Harlow about the Firewall issue, […] Click to continue reading this post

Southern California Strings Seminar

The group at UCLA is hosting the next SCSS, and it is on Friday. More details here. The schedule looks good:

9:30-11:00 Sera Cremonini (Texas A&M): “Probing the IR of hyperscaling violating geometries.”

11:15-12:45 Ken Intriligator (UCSD): “Aspects of 3d N=2 Chern-Simons-Matter Theories.”

12:45-2:15: Lunch

2:15-3:45: Daniel Harlow (Princeton): “On the Computational Complexity of Hawking Radiation”

4:00- 5:30: Eric D’Hoker (UCLA): “Supermoduli and supersymmery breaking”

Enjoy!

-cvj Click to continue reading this post

Sketchy Look

magazine_sketch_18th_May_2013On Saturday I decided to have a bit of simple relaxation at home, and sit on the patio with my notepad and some pencils and draw a likeness. I’d not done any practice from images for a while, and frankly my pencil work was very rusty and needed a workout.

So I dug out this month’s issue of a sewing magazine that I subscribe to (what?! well, it’s a long story… let’s move on) that happens to sometimes have interestingly lit and well reproduced photos of faces and sketched for a while.

It was fun (even with the slightly flawed outcome). (Click for a larger view.)

-cvj Click to continue reading this post

Something’s not quite right, perhaps?

thing_vs_thing Yeah. Scary, right? I woke up one morning to this result (see earlier posts here, here, and here) from a night of an intensive computer run. It was not meant to be a straight line, but pretty close to it, so I knew that something was wrong with my code. Took me a good long while to trace the problem, but I did in the end. My signal was being swamped by both […] Click to continue reading this post

Final

Well, I’ve got to say goodbye to another excellent group of students from my undergraduate electromagnetism class. We had the final today (starting at 8:00am – ack!), and given the lack of rioting, tears, and throwing of rotten fruit during the exam itself, I assume that it was not too bad an exam to sit. Of course, the real measure of what they thought will be how they did in the actual answering of questions, and I’ve not looked to see how that has turned out yet.

Again, I feel a bit sad since it was a good group of students and it was fun to teach them this material. While it is certainly good to move on to other things (I’ve too many projects I want to work on, as usual), I will miss the twice weekly classes with them. Highlights this year include (in no particular order):

(1) The thing I love to do when we are studying dipole radiation – taking the class outside (surprising them somewhat) to look up at the blue sky and connect why it is blue to the computation we just did, including understanding the pattern of the blueness […] Click to continue reading this post

Lines of Thought

So I’ve moved on to curved lines now, in case you’re wondering. 🙂 (See previous posts.) The last several days (the research parts) have been taken up with more computations. A lot of the time has been spent calibrating the programs, and trying to assess and understand and characterize the inevitable errors that show up, by running the programs and checking the resulting plots of data points against expectations shaped by hand calculations. Calculating on the train to and from work, I’ve filled several pages of my small notebook with computations, alongside sketches of some of my surroundings as usual (people mostly). As a result (fingers crossed) I think I’ve now understood all the key aspects of the results I’ve been getting, and have good numerical control of things. To get such control, I’ve had to push the error tolerance and the size of the grid of points I’m computing on to regimes where I’m back again to waiting for the better part of an hour for each data point. (One sets up the problem on the computer by making continuous variables, such as space and time, into discrete ones, forming a grid. The problem is then to use various […] Click to continue reading this post

A Much Shorter Straight Line

LinePlot2 How is the line coming along? It is very kind of you to ask (if indeed you were). Well, there it is to the left. (See the previous post for background.) In the end, I abandoned Maple since it was taking way too long to do each point, and just for the simple example. (When I tried to do one sample point of the complicated example it took 24 hours and I stopped it before it was done!) The point is that Maple does not easily […] Click to continue reading this post

A Very Long Straight Line

I’ve been multitasking in an interesting way. Sort of. I’ve reached a certain point with some computations I am doing that I cannot go beyond by analytic means. LinePlotThis means that I can’t extract the physics I need by doing algebra and other exact manipulations on paper any more. Progress can continue however by using numerical means, employing a computer to solve the highly non-linear equations and extract the juice. There are several steps involved, and ultimately, I want to determine how a certain physical quantity depends on another physical quantity. (I’m sparing you the trouble of knowing what the details of the physical quantities are, since it does not matter for the thing I am trying to tell you. It relates to quantum field theory, gravity, and string theory, which connects the two.)

I can see that dependence quite clearly if I simply plot a graph of one versus the other, and in this case I need the computer to work out what the points on that graph are. I actually don’t know the answer for the cases I really am interested in, nobody does (that’s why it is research!), and so that’s what I want to find. I want lots of points to get a nice smooth graph, so the computer has to compute a lot of points, and I need to run it for a long time since I want it to compute the points very accurately. So I wrote a program (in Maple) to work on the problem, studying just one […] Click to continue reading this post

TED Youth Talk – Hidden Structures of the Universe

cvj_TED_YouthYou might recall that last year I gave a talk at TED Youth, in their second year of short TED talks aimed at younger audiences. You’ll recall (see e.g. here and here) I made a special set of slides for it, composed from hundreds of my drawings to make it all in graphic novel style, and somehow trying to do (in 7 minutes!!) what the TED people wanted.

They wanted an explanation of string theory, but when I learned that telescopesI was the only person in the event talking about physics, I kind of insisted that (in a year when we’d discovered the Higgs boson especially!) I talk more broadly about the broader quest to understand what the world is made of, leaving a brief mention of string magnifytheory at the end as one of the possible next steps being worked on. Well, they’ve now edited it all together and made it into one of the lessons on the TED Ed site, and so you can look at it. Show it to friends, young and old, and remember that it is ok if you don’t get everything that is said… it is meant to invite you to find out more on your own. Also, as you see fit, use the pause button, scroll back, etc… to get the most out of the narrative.

I’m reasonably pleased with the outcome, except for one thing. WHY am I rocking […] Click to continue reading this post

How is that Supposed to Work, Exactly? (Part II)

Well, since some of you are curious about how the page might look in final form, given the (nicer than normal) rough I showed you a little while ago, I thought I’d show you. page_sample_inked(For those of you not following, this is part of the graphic science book project I’m slowly working on. More here.)

I got carried away and decided to properly pencil out the whole page and ink it fully, and then I painted the same panel as before. Now you can see more carefully rendered faces according to the design I chose for these characters, and you can also see the backgrounds of the setting a bit more. It is another real location, a very well known place in Europe. (Actually, I spent some days doing research online to try to reconstruct the details of the interior from tourist photographs, and reconstructed […] Click to continue reading this post

Changeover Time

start_scribbleIt’s that time again. I finish a notebook and start a new one. A new book is begun with writing my name and contact information in the front part, in case it gets lost, and an old one is ended with mixed feelings, and that ending is often a bit drawn out. Notebooks go around with me nearly everywhere, and have pieces of me in them in one shape or another, and so it is hard to stop carrying one and start a new one. I’ve got bits of computations, shopping lists, partial thoughts about projects, design sketches, doodles, snippets of silent conversations between me and another person at a concert or talk (writing it down is often less distracting to neighbours than a whisper), scribbled phone numbers, film, book or cd reminders, and of course lots of practice sketches and doodles on trains, planes, and in automobiles, done almost on a daily basis, sketches done in (and sometimes of) an event, or of a interesting place or structure. (You’ve seen some of them here on the blog.) Almost everything has a date written on the page, or on a page nearby, which is hugely valuable.

changeoverIt’s a combination of notebook, journal, playground for ideas, and more. It is a joy to just open it up and flip through it and see so much of the last few months of my life and thought spread out in ink and pencil (and sometimes watercolour). Sometimes I hit on a particularly successful or interesting (or both) drawing that I love to open up and look at from time to time. You can search the blog under “sketches” for things that were in previous books. For example, a few of my favourites from this book are: Sketch of C. Tyler during her talk, sketch during a committee meeting, airline sketch of a national treasure, other airline sketches, a nice grab of a face from the subway, another airline sketch.

All of that now gets put on a shelf, since the pages have run out. It is bitter-sweet, as I also like the analogue, finite nature of the whole business. It has a lot of life written […] Click to continue reading this post